fix(frontend) : add missing useTaskDocumentService imports

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/components/task/TaskModal.vue

@@ -217,6 +217,7 @@
 import type { Task, TaskWrite } from '~/services/dto/task'
 import type { TaskDocument } from '~/services/dto/task-document'
 import { useGiteaService } from '~/services/gitea'
+import { useTaskDocumentService } from '~/services/task-documents'
 import type { TaskStatus } from '~/services/dto/task-status'
 import type { TaskEffort } from '~/services/dto/task-effort'
 import type { TaskPriority } from '~/services/dto/task-priority'